Human and experimental toxicology of diquat poisoning: Toxicokinetics, mechanisms of toxicity, clinical features, and treatment

Abstract

Diquat (1,1′-ethylene-2,2′-bipyridinium ion; DQ) is a nonselective quick-acting herbicide, which is used as contact and preharvest desiccant to control terrestrial and aquatic vegetation. Several cases of human poisoning were reported worldwide mainly due to intentional ingestion of the liquid formulations. Its toxic potential results from its ability to produce reactive oxygen and nitrogen species through redox cycling processes that can lead to oxidative stress and potentially cell death. Kidney is the main target organ due to DQ toxicokinetics and redox cycling. There is no antidote against DQ intoxications, and the efficacy of treatments currently applied is still unsatisfactory. The aim of this work was to review the most relevant human and experimental findings related to DQ, characterizing its chemistry, activity as herbicide, mechanisms of toxicity, consequences of poisoning, and potential therapeutic approaches taking into account previous experience in developing antidotes for paraquat, a more toxic bipyridinium herbicide.

Successful extracorporeal membrane oxygenation support for severe acute diquat and glyphosate poisoning

“…The main mechanism of diquat toxicity is related to its redox cycle, inducing reactive oxygen species and reactive nitrogen species generation, oxidative stress, and cell death. [4,17–19] The precise mechanism of glyphosate poisoning is still unclear. Surfactants are considered the most toxic component in glyphosate.…”

“…The combined poisoning with diquat and glyphosate may cause severe mucosal damage including edema and hemorrhage. [4,5,17,21] Central nervous system symptoms include coma, epileptic seizures, and hemorrhage. [4,22] Shock and malignant arrhythmia may also occur in some cases.…”

“…[4,5,17,21] Central nervous system symptoms include coma, epileptic seizures, and hemorrhage. [4,22] Shock and malignant arrhythmia may also occur in some cases. [3,4,17,23] The occurrence of complications is dose-related.…”

“…[4,22] Shock and malignant arrhythmia may also occur in some cases. [3,4,17,23] The occurrence of complications is dose-related. The kidney is the main target organ and the main pathological changes involve tubular necrosis.…”

“…The kidney is the main target organ and the main pathological changes involve tubular necrosis. [1,4,17,24] Renal toxicity and pulmonary toxicity seem to be responsible for mortality. [9] Respiratory system symptoms include bronchial pneumonia and pulmonary edema.…”